from dasbus.connection import SessionMessageBus
bus = SessionMessageBus()

proxy = bus.get_proxy(
    "org.freedesktop.Notifications",
    "/org/freedesktop/Notifications"
)

id = proxy.Notify(
    "", 0, "face-smile", "My notification",
    "Hello World!", [], {}, 0
)

logging.info("The notification {} was sent.".format(id))